The simple pulse type power supply is known. It is a single phase device in which full power or no power is supplied to a load depending upon the part of a cycle of operation that is being instantaneously considered.
Plural phase power has been supplied to a pair of fluorescent lamps that illuminate a common area for the purpose of reducing visual flicker. Usually, an all-alternating-current apparatus has been used and transformer means has been employed to split the phase of a single-phase alternating-current source, or of a three-phase alternating-current source, to convert it to two-phase for supplying the two fluorescent lamps.